Brush and method of making same



April 3, 1956 B E NELSON ET AL 2,740,148

BRUSH AND METHOD OF MAKING SAME Filed Dec. 24, 1949 2 Sheets-Sheet 2 INVENToR woo/fs E. NELo/v 1- BY 2085A/ d. PETE/esoy 013m@ @JM 19 7 7 OBA/E545.

2,740,148 BRUSH AND METHD F MAKINGSAME Application December 24, 1949, Serial No. 134,904 22 Claims. (Cl. 15-181) This invention relates as indicated to a novel brush and method of manufacturing the same, and more particularly to a brush of the general type shown and described in Bickel et al. Patent No. 2,062,047 and Peterson Patent No. 2,480,877. Such brushes are commonly referred to as being of the twisted tuft type, the usual commercially available form comprising an annular disc having a plurality of holes therein through which tufts of wire bristle material are inserted and then doubled upon themselves and twisted together. Such brushes have found a Wide field of use, being particularly adapted for the removal of scale from metal surfaces and the like. Peterson Patent No. 2,480,877 discloses a preferred arrangement of the twisted tufts whereby a much improved and uniform brushing action is obtained.

Twisted tuft brushes of the type here under consideration have always been rather expensive of manufacture since each brush has had to be individually assembled, involving a good deal of hand work. Itis accordingly a primary object of our invention to provide a method of manufacturing brushes of the twisted tuft type which will be substantially continuous in operation and require a minimum of hand work or supervision.

It is frequently desired to provide a rotary brush having a relatively wide brush face, and in the past a number of sections have merely been mounted upon an arbor or the like in close side-by-side relationship to obtain this effect. It is another object of our invention to provide a method of manufacturing a rotary brush of the twisted tuft type of any desired axial width and in which adjacent tufts will be arranged mutually to support one another with consequent reduction in destructive vibration of the wire bristles to obtain longer brush life.

Still another object is to provide a twisted tuft rotary brush in which the bristle material is embedded in a resilient matrix. n

Other objects of our invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention then comprises the features hereinafter fully described and particularly' pointed out in the claims, the following description and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative', however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

Fig. l is a somewhat diagrammatic side elevational view illustrating the method of manufacturing a preferred embodiment of our new brush;

Fig. 2 is a top plan view corresponding generally to Fi l;

iig. 3 is an elevational view of an assembled rotary brush partly broken away to show the internal construction thereof;

Fig. 4 is a sectional view on a somewhat enlarged scale taken along the line 4-4 on Fig. 3; Y

Fig. 5 is a fragmentary detail view illustrating the tes Patent manner in which the desired number of turns' of our Fig. 6 is a fragmentary detail sectionall view takenA along the line 6 6 on Fig. 1 and` showing meansV for momentarily clamping the traveling brush strip during' the tuft twisting` operation;

Fig. 7 is an elevational view showingA the continuous, formation of twisted tuft brush strip especially adapted for use in cup brushes and the like;

Fig. 8 is a bottom plan view corresponding to Fig. 7;

Fig. 9 is a transverse sectional view through a cup brush assembly employing brushl elements produced in the manner illustrated in Figs. 7 and 8; and

Fig. 10 shows a similar transverse sectional view of a cup brush utilizing our new form of brush element embedded in a resilient supporting matrix.

Referring now more particularly to Figs. 1 6l of such drawing, we have provided for the production of a twisted tuft brush in continuous strip form, such strip being designed for edgewise circularization about a mandrel or arbor with the tufts of brush material extending radially. A continuous ilat steel strip 1 is punched at fairly closely spaced intervals to provide notches 2 therein. Such. notches terminate in circular openings 3 centrally of the strip and are beveled at 4 adjacent the edge of theA strip. Strip 1 travels from left to right as shown in Fig. l, being wound upon an arbor 5 driven by belt 6. Such arbor is provided with a plurality of longitudinally extending ribs 7 corresponding in their parallel spacingv to then distance between the respective notches 2 in the metal strip. When such strip is circularized about the arbor as shown, notches 2 are closed but the oppo-sed beveled portions 4 now cooperate to produce relatively small notches in the inner periphery of the circularized strip and such notches are engaged by longitudinally extending ribs 7 on arbor 5 to obtain the necessary traction to advance and deform the strip.

Prior to such circularization the strip passes between clamping mechanism comprising a fixed block itl and a laterally reciprocable clamping member 9. Member 9 is reciprocated at timed intervals temporarily to clamp strip l and arrest the advance of the same. A friction clutch drive for arbor 5 may be employed, or slipping of belt 6 may be relied upon. Preferably, however, the arbor will be driven intermittently in timed relation to the filling and twisting operation. An upwardly extending tapered finger F is adapted to be reciprocated to enter notch 2 to assist in arresting advance of stripl 1 but more particularly exactly to center opening 3- with corresponding. openings in the tuft twisting means. Also, insertion of such finger in the notch serves to prevent premature buckling of the strip when the bundle of brush material is broken (i. e. doubled about the strip) by upward movement of the twisting. nose as described below. The usual form of slotted twisting nose l0 will bridge strip 1 at this time, having openings 11 therethrough on opposite sides of the str'p aligned with one of the circular holes 3 in the latter. A tuft or bundle of bristle material 12 is then inserted through such pair of openings 11 and hole 3 and the twisting nose 10 next elevated to clearthe.

strip. When thus elevated, it will be rotated to twist the two doubled portions of the wire bristle bundle together to form the usual twisted tuft. As taught in Peterson Patent No. 2,480,877, such twisting nose may desirably be rotated in opposite directions with each succeeding tuft so that alternate tufts will be twisted in oppositev directions'. The finished brush will then be more uniform and superior in itsv brushing characteristics.

As turns of the circularized strip accumulate upon the arbor as shown in Fig. 2, one or more turns (or segments of turns) may automatically be severedv from theI following turns by means of shears comprising opposed assembled together in Figs. 3 and 4 to produce a superior rotary brush or Wheel. Each of the two individual turns is arranged with the opposed ends of its strip 1 abutting, and the two annular sections thus formed are brought into close side-by-side position with the tufts of one section staggered relative to the tufts of the other section whereby a more uniform brush face is obtained and the tufts mutually support one another, reducing deleterious vibration. A pair of identical clamping plates 17 embrace the inner peripheral portions of such assembled sections and are riveted together by means of inner tongues or anges 18 extending through the inner annular opening alternately from each clamping member and turned up at their ends to lock the same together. Each such member 17 may desirably include outwardly convex side portions 19 to accommodate the bristle material where the latter is doubled through openings 3, and inturned teeth 20 punched in from the sides of such clamping members overlie the radially outer edge of strip l reinforcing the latter against the effect of centrifugal force when the brush is in use.

It will be seen from the foregoing that we have provided a novel rotary brush of the twisted tuft type, the principal element of which is adapted to be continuously produced and circularized. The shape and size of notches 2 will, of course, depend on the diameter of the arbor about which the strip is to be circularized and also on the number of tufts to be employed per turn. The

angles initially defined by such notches 2 multiplied by the number of tufts per turn should total 360.

Since the brush material will ordinarily be twisted into tufts, various types of metal wire bristles will usually be employed. The bundles of brush material may, however, merely be doubled back on themselves without twisting, in some instances, particularly when they, or their base portions, are later to be embedded in a suitable plastic base or clamped between appropriate end plates. (See, for example, the description of the Fig. l0 construction below.) The base strip 1, while ordinarily of steel, may obviously be of other metals and even syntheticv plastic material if working conditions so indicate.

In one standard size of brush element, we employ steel strip one inch wide and one-eighth inch thick. This represents a great saving in scrap as contrasted to the circular discs previously used where such discs required to be punched from relatively wide steel strip. Waste metal was also produced in punching out the center arbor hole.

Our base strip, or retaining strip, is strong without being excessively heavy and when circularized to a particular diameter may be mounted upon selected adapters to accommodate different size arbors of brushing lathes. It is possible to place the holes 3 relatively close together so as to permit increased density of ll. The notches 2 have apices ordinarily lying within the areas of the respective holes 3 so that upon deforming the strip in its own plane (i. e. edgewise) such holes will close somewhat. Since these holes are thus somewhat oversize at the time the bundles of bristle material are inserted, such insertion is considerably facilitated.

The teeth will preferably be inclined or beveled on their under edges so as to engage and cam down the outer-periphery of the circularized strip 1 (Fig. 4). In fact, such teeth may even be caused slightly to indent such outer periphery, ifl desired.

r The small notches formed by the beveled portions 4 of notches 2 when the strip is circularized are not only of assistance in obtaining proper traction on arbor 5 but also may be employed to key the finished brush on the arbor of a brushing lathe or the like. While it is preferred to sever the circularized brush element into a desired number of turns in the manner above described, an alternative method is to nick or groove a side of strip 1 at selected intervals. The circularized strip may then be broken apart at such nicks by lateral bending. While single turns of our new brush element will commonly be employed alone or in side-by-side relationship with other single turns, a plurality of helically wound turns may be employed if desired.

Referring now more especially to Figs. 7-l0 inclusive of the drawing, we there illustrate a method of continuously producing twisted tuft brush elements especially suitable for use in cup brushes and the like. A row of holes 21 is punched in a continuous flat metal strip 22 which is advanced from left to right as viewed in Figs. 7 and 8. Tufts or bundles of Wire bristle material 12 are inserted through such holes, doubled back and twisted upon themselves in the same manner described above. Strip 22 is, however, not notched and is instead circularized substantially flatwise in a helical manner with the tuft bearing edge of the strip inclined slightly outwardly. Such helically circularized tufted strip will ordinarily be severed into single turns as it is produced which may then be assembled into an annular stamping 23 having inturned teeth 24 overlying the edge of strip 22 to hold the latter in position. Two individual turns of the circularized tufted strip will preferably be utilized as shown in Fig. 9, the inner turn being of course of somewhat smaller diameter than the outer turn and arranged so that the twisted tufts carried thereby will be staggered relative to and lie partially between the tufts of the outer turn. Base strip 22 of such inner turn is held in place by means of an inner annular metal ring 25, the lower edge portion 26 of which is turned up and engages a Washer or spacer ring 27 inserted beneath the inturned lip 28 of the inner channel wall 29 of annular channel-form stamping 23. Teeth 30 punched in from ring 25 overlie the edge of the inner turn of the brush` strip 22 to secure the latter in place.

Brush strip of the type last above described may alsol be wound spirally for mounting in a suitable receptacle to serve as an end brush. Infact, a large variety of shapes and forms of brushes will at once occur to those skilled in the art as adapted to the employment of our new brush strip. t

In the Fig. l0 embodiment, a single turn of the brush strip 22 is seated within the annular generally channelform stamping 31 provided with retaining teeth 32 similar to teeth 24. A small angularly deformed ring 33 reinforces the inner peripheral wall 34 of stamping 31 but no retaining member similar to annulus 25 is employed. Instead, a suitable elastomer 35 such as neoprene is molded about the brush material to embed the same and also ll the channel defined by stamping 31. Such resilient material extends substantially to the ends of tufts 12 and has the effect of accentuating the harshness of the latter while at the same time preventing undue vibration and consequent early fracture of the brush material strands.

The plastic material employed to embed the stranded brush material may comprise rubber or neoprene (a synthetic rubberlike material) containing a large amount of a iiller such as Whiting which has the effect of causing the matrix to crumble back at the working face of the brush to expose short tips of the wire bristles. Reference may be had to the co-pending application of Ruben O. Peterson,y Serial No. for further details and examples of appropriate brush material and matrix material. We have found that brush i strip of the type disclosed in the present application is particularly `suited for embedding in this manner.

With the resilient plastic forming a part of the hub 50,850, filed September 23, i948,y

proper, as at in Fig. 9, the brushing tool becomes substantially self-centering. The radial form ofy brush shown in Figs. 3 and 4 may be similarly embedded, the resilient plastic not only preventing undesiredconcentrations of vibration and the like but also protecting the brush material from corrosion.

The term wire as employed herein and in the claims is intended to include not only metal wire but also equivalent stranded brush material which may be doubled and twisted upon itself and caused to retain such conformation. Similarly, the term circularize" is used to denote bending of the strip to annular form although it will be appreciated that the resultant configuration may be circular, helical, spiral, etc., as desired.

During such bending operation as illustrated in Fig. l the outer edge of the tutt-supporting' strip will of course be somewhat stretched whereas the inner edge will be shortened by closing up of the notches which relieve such edge. The provision of such notches greatly reduces the amount of stretching of such outer edge `that would otherwise be required and also prevents buckling of the inner edge.

While such notches may be provided intermediate the holes through which the tufts are inserted it is preferred that they correspond to and join such holes, as shown. When such preferred construction is employed the circularization of the strip tends to close such holes somewhat, more tightly gripping the brush material. Consequently, insertion of the brush material in the holes is facilitated since such tufts need not initially entirely lill the same. For this reason also, while the brush material may be inserted after circularization of the strip as shown in Fig. l, it is both more convenient and results in a better brush element to insert the material at the stage there indicated.

The notches are tapered on an angle ordinarily having its apex in the center of the corresponding tutt-receiving hole. As above indicated, such angle is determined by the number of tufts per turn of strip, the notches being closed when the strip is deformed in its own plane so that only radial cuts remain to show their former existence.

Other modes of applying the principle of the inven tion may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

We therefore particularly point out and distinctly claim as our invention:

1. The method of producing a brush element which comprises longitudinally advancing a continuous fiat metal strip, punching a series of closely spaced holes in` such strip, inserting bundles of wire brush material through such holes so that the respective ends of each such bundle protrude on opposite sidesv of such strip, doubling and twisting such bundles on themselves' about the edge of such strip to form twisted tufts extending generally parallel to one another in the same direction from such supporting strip, circularizing such strip about an axis generally parallel to such tufts and the plane of such strip but with such strip and tufts inclined at a slight outward angle to such axis, and securingV such circularized strip in an annular cup-shaped base.

2. The method of producing 'a brush element which comprises longitudinally advancing a continuous iiat metal strip, punching a series of closely spaced holes in such strip, inserting bundles of wire brush material through such holes so that the respective ends of each such bundle protrude on opposite sides of such strip, doubling and twisting such bundles on themselves about the edge of such strip to form twisted tufts extending generally parallel to one another in the same direction from such supporting strip, and circularizing such strip about an axis generally parallel to such tufts and the plane of such strip but with such strip and tufts inclined at a slight outward angle to such axis. i *A 3. The method of producing a brush element which comprises advancing a continuous metal strip', punching a series of closely spaced holesr in' such strip, inserting bundles of wire brush material through such holes, dou`v bling and twisting such bundles on themselves I edge of such strip to form twisted tuftsv extending' gener: ally parallel to one another from such supporting strip, and circularizing such strip about an' axis generally p'ar-v allel to such tufts. n

4. The method of producing a brush element compris-` ing progressively advancing a continuous thin flat strip of supporting material, punching a series of closely spaced holes in such strip', inserting bundles of brush material through such holes, doubling such bundles back on themselves about the edge of s'uch strip, twisting such individual doubled bundles to form twisted tufts extending gen'- erally parallel to one another from such supporting strip, and circularizing such strip.v v

5. The method of producing a brush element compris-r ing progressively advancing a continuous thin tiat strip of supporting material, punching a series of closely spaced holes in such strip, inserting lengths of brush material through such holes, doubling such brush material back on itself about one edge of `such strip so that the ends thereof extend in the same direction relieving' the other edge of such strip at inervals therealong, c'ircularizin'g such strip about an axis generally normal to its flat plane' so that such brush material extends generally radially outwardly therefrom, and severing such circulari'zed strip into desired sections with the ends of each such section opposed to` one another. n

6. The method of producing a' brush element which comprises notching an edge ofv a strip of supporting material to provide a series of adjacent notches therein, in`- serting lengths of brush material in such notches extending transversely of such strip, doubling' such material back on itself so that the ends thereof extend in thesaine direction and away from such notches, and deforming such strip to close such notches and thereby secure such' material therein.

7. The method of producing a brush element which' comprises notching an edge of a strip of supporting material to provide a series of adjacent notches therein, inserting lengths of brush material in such notches 'extend'- ing transversely of such strip, doubling such material about such strip with the ends from such notches and twisting such material on itself to form twisted tufts extending generally parallel to one another, and deforming such strip in the plane thereof to close such notches.

8. The method of producingv a brush elementl which comprises advancing a continuous flat metal strip, punch-v ing a series of closely adjacent notches in an edge of such strip, such notches having enlarged apices, inserting bun dles of Wire brush material through such apices of such notches, doubling such bundles about such strip and twisting on themselves to form twisted tufts extending generally parallel to one another, and circularizin'g such strip about an axis generally normal to the plane of such strip to close such notches, with such tufts thereupon extending generally radially.

9. The method of producing avbrush element which comprises advancing a continuous ilat metal strip, punching a series of closely adjacent notches in an edge of such strip, such notches having enlarged apices, inserting bundles of wire brush material through such apice's of such notches', doubling such bundles about such strip and twisting on themselves to form twisted tufts extending generally parallel to one another, circularizing such strip about an axis substantially normal to the plane of such strip" to close such not hes, with such tufts Atliertepc'nt extending generatly radially, severing stica eiclarzed about the thereof vextending away" wire brush material inserted through such holes and doubled and twisted on themselves to form a series of twisted tufts, said strip being circularized about an axis generally parallel to the plane thereof with such tufts extending generally parallel to one another in the same direction; teeth carried by said stamping projecting closely over said circularized strip seated therein to secure said brush element; and a resilient body of an elastomer surrounding and embedding such tufts.

il. A brush comprising an outer annular cup-shaped metal stamping; a circular brush element seated in said stamping comprising an elongated dat metal strip having a series of holes punched therethrough, and bundles of wire brush material inserted through such holes and doubled about the same edge of said strip and twisted on themselves to form a series of twisted tufts, said strip being circularized about an axis generally parallel to the plane thereof to form a generally cylindrical bristle tuftsecuring element with such tufts extending generally parallel to one another in the same direction; and teeth carried by said outer stamping projecting over said circularized strip seated therein to secure said brush element.

12. A brush element comprising a narrow elongated at metal strip having a series of holes punched therethrough, and bundles of wire brush material inserted through such holes and doubled and twisted on themselves about the same edge of said strip to form a series of twisted tufts, said strip being circularized about an axis generally parallel to the plane of said strip with such tufts extending generally parallel to one another in the same direction and with the ends of said elongated strip opposed to each other to form a generally cylindrical bristle tuft-securing element.

13. The method of producing a brush element which comprises advancing a continuous at metal strip, punching` a series of closely adjacent tapered notches in an edge of such strip, such notches terminating in circular holes and the outer edges of such notches being further beveled, inserting bundles of wire brush material through such holes, doubling such bundles about such strip and twisting on themselves to form a series of twisted tufts extending generally parallel to one another, circularizing such strip edgewise about a rotating arbor to close such notches, except for such beveled portions, with such tufts thereupon extending generally radially, and severing such circularized strip into desired sections, such beveled portions of such notches engaging traction means on such arbor to advance and circularize such strip.

14. A ro-tary brush comprising two annular brush sections assembled in close side-by-side relationship, each section being provided with radially extending tufts of brushing material, the tufts of one section being staggered relative to the tufts of the other section to afford mutual support and a uniform brush face, each said section comprising an elongated fiat metal strip having a series of tapered notches in an edge thereof, such notches being enlarged at their apices, bundles of wire brush material extending through such enlarged apices of such notches, doubledabout said strip, and twisted upon themselves to form a series of twisted tufts, said strip being circularized to close such notches with such tufts extending generally radially, and apair of annular clamping members embracing opposite sides of said two-section assembly and provided with teeth extending inwardly over said circularized strip to secure the same against the effect of centrifugal force in use. 1 15. A brush element comprising an elongated fiat metal strip having a seriesl of holes therethrough, said strip being of wire brush material deformed by edgewise circularization, cuts in the innerv peripheral edge of said circularized strip extending radially to said holes and formed by closing of notches in such edge thereby to facilitate such deformation, and bundles inserted through such holes and twisted upon themselves to form a series of generally radially extending twisted tufts.

16. A brush element comprising an elongated at metal strip of denite length having a series of holes therethrough, said strip being deformed by edgewise bending in its own general plane, and brush material inserted through such holes and twisted upon itself about the radially outer edge of said strip 17. An annular brush element comprising an elongated flat metal strip circularized in its own plane with the ends of said strip opposed to each other, the inner periphery of said circularized strip having a plurality of cuts therein and the outer periphery being stretched, said strip having a series of holes therethrough, and brush material inserted through such holes and twisted upon itself about said strip to form a series of radially extending tufts.

18. The method of forming a brush element which comprises inserting brush material through openings in an elongated strip of supporting material, twisting such brush material to form a series of twisted tufts extending generally parallel to one another from one edge of such strip, relieving the other edge of such strip, and deforming such strip by circularizing the same in its own plane, stretching the edge from which such tufts extend and shortening such relieved edge.

19. A brush element comprising an elongated at strip of sheet material having a plurality of deep notches in one edge thereof, and brush material extending through such notches and doubled about said strip on the side away from such notches, said doubled brush material being secured together closely beyond said strip to prevent escape from such notches.

20. A brush element comprising a narrow elongated hat strip of sheet material having a series of longitudinally spaced apertures therethrough, one edge of said strip having cuts therein to relieve the same and said strip being circularized in itsown plane with such relieved edge defining the inner periphery of the circle, and bundles of brush material extending through such apertures with the respective end portions of each said bundle forming tufts extending radially outwardly beyond the outer edge of said circularized strip.

21. The method of producing a rotary brush element which comprises longitudinally advancing an elongated narrow length of flat strip material, punching a series ofholes therethrough spaced longitudinally of such strip, inserting lengths of brush material through such holes, doubling such material back on itself about the same edge of such strip so that the end portions thereof extend in the same direction, twisting such end portions together, and circularizing such elongated strip.

22. A rotary brush element comprising a ilat sheet material ring having radially inner and outer edges, said ring having a plurality of deep notches in the inner edge thereof and brush material extending through such notches and doubled about said ring to extend generally radially outwardly therefrom, said doubled brush material being secured together closely beyond the outer peripheral edge of said ring.

- References Cited in the le of this patent UNlTED STATES PATENTS 

